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Has anyone ever done a scientific study on how fast small children are? I swear to dog, that when a 3 or 4 year old gets some speed on and goes running towards a busy road, they are faster than Usain Bolt. If they could keep up that initial burst of speed they do over a significant amount of time, and not get distracted by people walking dogs on the side of the road, they could easily run a marathon in 10 minutes.